Aminopolyamide-acrylamide-polyaldehyde resins having utility as wet and dry strength agents, retention aids and flocculants and a process of making and using them and paper made therefrom

ABSTRACT

Disclosed is a novel aminopolyamide-acrylamide-polyaldehyde resin useful in the paper making art to enhance the wet and dry strength of paper. Small amounts of the resin can also be used as a retention aid for mineral fillers in paper and as a flocculant for suspended matter.

0 United States Patent 1 1 3,607,622

[72] lnventor HerbertH.Espy [50] FieldofSearch 260/72, Fairfax,Wilmington, 850; l62/l64, 167,166,169, 168, 189, 190; 21 AppLNo. 747,090210 5251 22 Filed July24,l968 [45] Patented Sept.2l,l97l [56]ReferencesCited [73] Assignee Hercules Incorporated UNITED STATESPATENTS wllmmgwninel- 2,616,818 11 1952 Azorlosa 260 72x 2,886,557 51959 T316: 260/72 3,420,735 1/1969 Conteetal. 162/167 [54]AMlNOPOLYAMIDE-ACRYLAMIDE- POLYALDEHYDE RESINS HAVING UTILITY AS WET ANDDRY STRENGTH AGENTS, RETENTION AIDS AND FLOCCULANTS AND A PROCESS OFMAKING AND USING THEM AND PAPER MADE THEREFROM 22 Claims, N0 Drawings[52] US. Cl 162/167, l62/l 64, 210/54, 260/72 R, 260/850 [5 1] Int. ClD2lh 3/58,

C02b 1/20, C08g 9/02 Primary Examiner-S. Leon Bashore AssistantExaminer- Frederick Frei AttorneyCharles L. Board ABSTRACT: Disclosed isa novel aminopolyamide-acrylami de-p0lyaldehyde resin useful in thepaper making art to enhance the wet and dry strength of paper. Smallamounts of the resin can also be used as a retention aid for mineralfillers in paper and as a flocculant for suspended matter.

AMINOPOLYAMIDE-ACRYLAMIDE-POLYALDEHYDE RESINS HAVING UTILITY AS WET ANDDRY STRENGTH AGENTS, RETENTION AIDS AND FLOCCULANTS AND A PROCESS OFMAKING AND USING THEM AND PAPER MADE TIIEREFROM This invention relatesto wet strength resins, the process of incorporating them into paper andthe paper so treated.

Various resins which impart wet strength to paper are known in the art.However, most of the prior art resins are of the permanent type, i.e.,paper treated with them retains its wet strength long after immersion inwater, which is desirable in packaging materials but presents a disposalproblem. A few resins are known which impart temporary wet strength andwould thus be suitable for sanitary or disposable paper uses, but eachof them suffers from one or more serious drawbacks. For example, theirwet strength efficiency is seriously decreased by alum, they are easilyattacked by mold and slime, they can only be prepared as dilutesuspensions or they must be sized into preformed paper because they arenot substantive to pulp.

it is an object of this invention to provide resins which impart bothdry and wet strength to paper.

It is a further object of this invention to-provide wet strength resinssuch that paper treated with them loses its strength on prolongedimmersion in water such as on disposal in sanitary systems, andfacilitates the handling of broke in the paper mill.

It is a further object of this invention to provide resins which imparttheir ultimate wet strength on drying alone without curing and aresubstantive to pulp without sizing.

It is a further object of this invention to provide wet strength resinswhich can be prepared in high solids concentrations.

It is a further object of this invention to provide wet strength resinswhich are not easily attacked by mold and slime growth.

It is a further object of this invention to provide wet strength resinswhich are more stable towards gelation on storage.

It is a further object of this invention to provide wet strength resinswhose efficiency is not seriously reduced by alum.

It is a further object of this invention to provide resins which act asretention aids for mineral fillers in paper and as flocculants andprecipitants for suspended matter.

Now in accordance with this invention these objectives and many othershave been achieved by preparing a wet strength resins from anaminopolyamide, an acrylamide and a polyaldehyde.

The wet strength resins of this invention are prepared by l) reacting anaminopolyamide, containing primary and/or secondary amine groups, withan acrylamide and (2) reacting the resulting adduct with a polyaldehyde.

Any aminopolyamide containing at least one primary or secondary aminegroup and resulting from the condensation of a polyalkylene polyaminewith an organic polybasic acid can be used in preparing the resins ofthis invention. The polyalkylene polyamines which can be used to preparethe aminopolyamides will have the general formula alkyl radicals.Typical polyalkylene polyamines are diethylenetriamine,dipropylenetriamine, triethylenetetraamine, tetraethylenepentaamine,pentaethylenehexaamine, imino-bis(3-aminopropyl)amine,bis(3aminopropyl)ethylenediamine, bis(2-aminoethyl)-l,3- diaminopropane,bis(3-aminopropyl)-l,3-diaminopropane, N,N-dimethyl-diethylene-triamine, tris( 2- aminoethyl)amine, andpolyethyleneimine. Typical of the polybasic acids which can be used inthe preparation of these compounds are the saturated aliphatic acidssuch as succinic, glutaric, 2-methylsuccinic, adipic, pimelic, suberic,azelaic, sebacic, hendecandioic, dodecandioic, 2-methylglutaric, 3,3-dimethylglutaric and tricarboxypentanes such as 4-carboxypimelic; thealicyclic saturated acids such as 1,2-cyclohexanedicarboxylic,l,3-cyclohexanedicarboxylic, l,4-cyclohexanedicarboxylic andl,3-cyclopentanedicarboxylic; the unsaturated aliphatic acids such asmaleic, fumaric, itaconic, citraconic, mesaconic, aconitic andhexene-3-dioic, the unsaturated alicyclic acids such asA-cyclohexenedicarboxylic; the aromatic acids such as phthalic,isophthalic, terephthalic, 2,3-naphthalenedicarboxylic,benzene-1,4-diacetic, 4- methylpjrthalic and trimellitic; and theheteroaliphatic acids such as diglycolic, thiodiglycolic,dithiodiglycolic, iminodiacetic, and methyliminodiacetic. It will beunderstood that esters, amides of lower amines, and anhydrides of theabove acids can be reacted with the above polyalkylene polyamines togive equivalent aminopolyamides.

The condensation reaction can be carried out by heating the polyalkylenepolyamine with the polybasic acid at a temperature of from about C. toabout 250 C. Optionally the reaction will be carried out in a diluent toaid in mixing and absorb the heat of neutralization of the acid by theamine. Care should be taken not to use too great an excess of acid lestirreversible gelation of the polyamide occur and all the amine groups beconverted to amides with no amine left for later reaction. In generalfrom about 0.5 to about 2.0, preferably from about 1.0 to about 1.3moles of polyalkylene polyamine per mole of acid will be used. Thecourse of the reaction can be followed by monitoring the melt viscosity.The reaction will ordinarily be continued until the reduced specificviscosity of the polyamide lies in the range of 0.05 to 0.5. Reducedspecific viscosity is defined herein as nsp/c measured at 25 C. inaqueous one molar ammonium chloride, where F20 percent (weightpolymer/volume solution).

As stated above, in the preparation of the resins of this invention theaminopolyamide is reacted with an acrylamide, including lower alkylsubstituted acrylamides such as methacrylamide, a-ethylacrylamide, andcrotonamide. Most preferably, a sufficient amount of the acrylamide willbe used to react with substantially all of the amine groups in theaminopolyamide. In practice an excess of acrylamide helps to drive thecarbamidoethylation of the amines to substantial completion in areasonable time. The reaction between the aminopolyamide and acrylamidecan be carried out at any temperature between about 20 C. and theboiling point of the reaction mixture at the solids concentration used.Temperatures between about 60 C. and about 1 10 C. are most preferred. Ahigh pH during the reaction is favored since this frees the amine groupsfrom their salts. Ordinarily the natural pH of the aminopolyamidesolution is satisfactory but it may be adjusted if necessary.

If desired a lightly alkylated resin can be produced by adding a smallamount of an alkylating agent, such as an epihalohydrin or alkylsulfate, either before, during or after the reaction of theaminopolyamide with the acrylamide. If the alkylation is carried outbefore reaction with an acrylamide, a few of the secondary amine groupsin the aminopolyamide molecule will be converted to tertiary amines orquaternary salts. If it is added after the formation of theaminopolyamideacrylamide adduct, it will substitute itself in the placeof a few acrylamides. It should be pointed out that alkylation is 'notessential to the process of this invention and excellent results areachieved when using resins which have not been alkylated.

The final reaction in the preparation of the wet strength resins of thisinvention is between the aminopolyamide acrylamide adduct and apolyaldehyde. Typical polyaldehydes which may be used in the finalreaction are glyoxal, malonie aldehyde, succinic aldehyde,glutaraldehyde, adipic aldehyde, Z-hydroxyadipaldehyde, pimelicaldehyde, suberic aldehyde, azelaic aldehyde, sebacic aldehyde, maleicaldehyde, fumaric aldehyde, dialdehyde starch, polyacrolein,phthalaldehyde, isophthalaldehyde terephthalaldehyde,1,3,5-triformylbenzene, and 1,4-diformylcyclohexane. This reaction isgenerally carried out at a pH of from about 5 to about and a temperaturein the range of from about 20 to 80 C. Mole ratios of polyaldehyde toacrylamide in the aminopolyamideacrylamide adduct will be between about0.05 and about 5.0, most preferably between about 0.1 to about 3.0. Theresulting wet strength resin will have a Brookfield viscosity of fromabout 5 c.p.s. to about 200 c.p.s. as determined on a Brookfield ModelLVE viscometer using a No. l spindle rotating at 60 rpm.

When using the wet strength resins of this invention in papermaking,they can be added at any time before, during or after the paper isformed. For example, the resin can be added before or after the refiningof the pulp, at the fan pump or head box, or by spraying on the wet web.The resin can also be added to preformed paper by tub sizing or sprayingon the dried paper sheets. In most commercial papermaking it will bepreferred to add the resin at the fan pump or head box in the form of anaqueous solution of up to percent solids. Various amounts of the resincan be used. When used to impart wet strength, the amount of resin addedwill be sufficient to result in a paper containing from about 0.05percent to about 5 percent by weight based on the weight of the paper.When used purely as a retention aid and no wet strength is desired, lessthan 0.05 percent by weight based on the weight of the paper can beused. The actual amount for any specific purpose can be easilydetermined by one skilled in the art. As stated above, no heat curing isrequired with the resins of the instant invention since they developtheir optimum strength on normal drying. They can be added to paper overa wide range of pH values. However, best results are obtained by addingthe resin to the paper at an acid pH of from about 1 to about 8 mostpreferably from about 3 to about 6.

Other ingredients can be used in conjunction with the wet strengthresins of this invention. The additives or ingredients commonly used inpapermaking can be used here also as for example alum, rosin size,coating colors, mineral fillers, starch, casein, etc. The presence ofother ingredients is not essential to this invention and excellentresults are achieved when using only the wet strength resins of thisinvention.

It will be obvious to those skilled in the art that the wet strengthresins of this invention can be incorporated into various types of papersuch' as kraft paper, sulfite paper, semichemical paper, etc. bothbleached and unbleached. While the resins can be used in various typesof paper, their advantages will be most sought in paper toweling orpaper tissues such as toilet and facial tissues.

The following examples will serve to illustrate the invention, parts andpercentages being by weight unless otherwise indicated.

EXAMPLE 1 This example shows the preparation of and use in papermakingof a typical wet strength resin in accordance with this invention.

To a mixture of 340.5 parts of tetraethylenepentamine and 75 parts ofwater is added 219 parts of adipic acid. The resulting mixture is heatedgradually to 170 C. and held between 170 and 177 C. for 5.2 hours duringwhich time the original water added and the water formed in the reactionis allowed to distill off. At the end of this time the mixture is cooledto 144 C. and diluted with about 492 parts of warm water. The resultingsolution contains approximately 49 percent total solids and has areduced specific viscosity of about 0.33. To 457.5 parts of the abovesolution is added 438.5 parts of water followed by 213 parts ofacrylamide. The resulting mixture is heated to 70 C. a nd held between70 and 7 5 C for two hours and then cooled. The thus cooled solutioncontains about 40.1 percent total solids. To 72.8 parts of the aboveaminopolyamideacry1amide adduct solution is added 73.2 parts of waterand the pH adjusted to 7.0 by adding 5.4 parts of 9.66 normal (37percent) sulfuric acid. To the thus acidified solution is added 29 partsof 40 percent aqueous glyoxal and the resulting mixture heated to 50 to55 C. After 45 minutes the viscosity of the mixture reaches aGardner-Holdt value of about K (determined using a sample cooled to 25C.). The resin solution is diluted with 97 parts of water, cooled, andadjusted to a pH of 5.0 with sulfuric acid. The resulting wet strengthresin solution contains about 15.5 percent total solids and has aBrookfield viscosity of about 41.4 c.p.s. at 25 C. After storage for 90days at room temperature a sample of the wet strength resin solutionshows no signs of mold or slime.

Rayonier bleached kraft pulp is beaten in a cycle beater to aSchopper-Riegler freeness of 750 cc. Portions of this pulp, adjusted toa pH of 4.5 with sulfuric acid, are added to the pro- .portioner of aNoble-Wood handsheet forming machine. Samples of the above wet strengthresin are added to the proportioner in amounts of 0.5 percent, 1percent, and 2 percent resin solids by weight of pulp solids. The pulpis then formed into handsheets of about 40 pounds per 3,000 square footbasis weight and dried for one minute at a temperature of 1 10 C. Acontrol handsheet is prepared exactly as described above except itcontains no wet strength resin. The resulting handsheets afterconditioning at a temperature of F. and 50 percent relative humidity forover 24 hours are tested for dry tensile strength and wet tensilestrength after soaking for 10 seconds in distilled water. The wettensile strength expressed as a percentage of dry tensile strength istabulated below:

Percentage of Resin Wet Tensile Percent Contained in Paper of DryTensile None 1.5

EXAMPLE 2 "treated with 58 parts of 40 percent aqueous glyoxal. The

resulting mixture is heated to 50 C. and held between 50 and 55 C. for48 minutes during which time the viscosity reaches a Gardner-Holdt valueof about L. The resulting wet strength resin solution is diluted withabout 328 parts of water cooled to 25 C. and the pH adjusted to about4.9 with sulfuric acid. The resulting solution contains about 9.3percent solids and has a Brookfield viscosity of about 7.7 c.p.s. at 25C. After storage for days at room temperature a sample of the wetstrength resin solution shows no signs of mold or slime.

Bleached kraft paper is prepared using the above wet strength resin asdescribed in Example 1. Samples of the thus prepared paper are testedfor dry and wet strength also as described in Example 1. The wetstrength, expressed as a percentage of dry strength is tabulated below.

Percentage of Resin Wet Tensile Percent Contained in Paper of DryTensile None 1.8 0.5 17.1 1.0 21.3

EXAMPLE 3 This example shows the preparation and use of a wet strengthresin prepared from triethylenetetramine.

To a resin kettle containing 142 parts of triethylenetetramine is added146.1 parts of adipic acid. The mixture is heated to 170 C. withstirring and maintained between 170 and 173 C. for 69 minutes. The resinmelt is then cooled to 140 C. and diluted with about 234 parts of warmwater. The resulting solution contains approximately 51.4 percent totalsolids and has a reduced specific viscosity of about 0193. To 124.5parts of the aminopolyamide solution is added 131.5 parts of water alongwith 35.6 parts of acrylamide. The resulting mixture is heated at 70 to75 C. for 2 hours and then cooled. The resulting mixture is heated at 70to 75 C. for 2 hours and then cooled. The resulting solution containsapproximately 35.1 percent solids. To 169.8 parts of the aboveaminopolyamideacrylamide adduct solution is added 8.8 parts of water.The pH is adjusted to 7.4 with sulfuric acid and then treated with 43.6parts of 40 percent aqueous glyoxal 2 solution. The resulting mixture isheated to 50 C. and maintained at this temperature for 56 minutes. Atthe end of this time the Gardner-Holdt viscosity is equal to about E atC. The resulting wet strength resin solution-is diluted withapproximately 288 parts of water, cooled and its pH adjusted to 4.8 withsulfuric acid. The resulting product contains approximately 14.9 percentsolids and has a Brookfield viscosity of 14.4 c.p.s. at 25 C. Afterstorage for 90 days at room temperature, a sample of the product showsno signs of mold or slime.

Bleached kraft paper is prepared from the above described wet strengthresin as described in Example 1. Wet strength tests are carried out alsoas described in Example 1. The results of these tests are tabulatedbelow:

Percentage of Resin Wet Tensile Percent This example shows thepreparation and use of a wet strength resin prepared from dodecandioicacid.

To a mixture of 43.5 parts of tetraethylenepentamine and 10 parts ofwater is added 46.1 parts of dodecandioic acid. The reaction mixture issparged with nitrogen and heated to a kit temperature of 170 C. Thereaction is maintained between 170 C. and 190 C. for 45 minutes. Thereaction product is then decanted and allowed to cool. To a solution of57.5 parts of the above solid aminopolyamide in about 136.6 parts ofmethanol is added 42.7 parts of acrylamide. The resulting mixture isboiled under reflux for 3 hours, then the solvent is stripped undervacuum at a maximum temperature of about 72 C. The resulting adduct hasa total solids content equal to about 86.2 percent. To 31 parts of theaminopolyamide acrylamide adduct is added 85.7 parts of water and thewhole adjusted to a pH of approximately 7.2 with sulfuric acid. Themixture is then treated with 23.2 parts of 40 percent aqueous glyoxaland heated to 50 C. After 35 minutes at a temperature of between 50 and53 C. the viscosity of the mixture reaches a Gardner-Holdt value ofabout L. The resulting resin is diluted with 100 parts of water, cooledto 25 C. and adjusted to a pH of4.9 with sulfuric acid. The final resinproduct solution has a total solids content of approximately 16 percentand a Brookfield viscosity of about 18.1 c.p.s. at 25 C. After storagefor 90 days at room temperature, a sample of the resin product solutionshows no signs of mold or slime.

Bleached kraft paper is prepared using the above wet strength resin asdescribed in Example 1. Samples of the thus prepared paper are testedfor wet strength, also as described in Example 1, and the resultstabulated below.

Percentage of Resin Wet Tensile Percent This example shows thepreparation and use of wet strength resin prepared from succinic acid.

To a mixture of 181.8 parts of tetraethylenepentamine and 50 parts ofwater is added 94.5 parts of succinic acid. The mixture is heated to 170C. with stirring while being sparged with nitrogen. After 4 hours at atemperature between 170 and 175 C. the hot product is decanted into apan and allowed to cool. To a solution of 54.3 parts of theaminopolyamide in 163 parts of water is added 56.9 parts of acrylamide.The reaction mixture is heated to 75 C., held there for 2 hours and thencooled. The resulting solution contains approximately 41.9 percent totalsolids. To 66.4 parts of the above solution of aminopolyamide-acrylamideadduct is added 79.6 parts of water. The pH of the mixture is adjustedto 7.2 using sulfuric acid. The mixture is then treated with 29 parts of40 percent aqueous glyoxal. heated to 50 C., and maintained between 50and 55 C. for 170 minutes. The resin is cooled, diluted with 81 parts ofwater and adjusted to a pH of 5.0 using sulfuric acid. The resultingsolution of wet strength resin contains approximately 15.2 percent totalsolids. After storage for 90 days at room temperature, a sample of thewet strength resin solution shows no signs of mold or slime.

Bleached kraft paper is prepared using the above resin as described inExample 1. Wet strength tests are carried out also as described inExample 1. The results are tabulated below.

Percentage of Resin Wet Tensile Percent This example shows thepreparation and use of a wet strength resin prepared from itaconic acid.

To a mixture of 1667 parts of tetraethylenepentamine and 40 parts ofwater is added 104.1 parts of itaconic acid. The resulting mixture isheated to 171 C. and maintained between 168 and 188 C. for 184 minutes.The product melt is decanted and allowed to cool. The reduced specificviscosity of the aminopolyamide is approximately 0.16. To a solution of141.7 parts of the above aminopolyamide in 328.3 parts of water is added142.2 parts of acrylamide. The resulting mixture is heated to between 70and C. maintained at that temperature for approximately 2.75 hours, thencooled. The resulting solution contains approximately 45 percent solids.To 63.2 parts of the aminopolyamide-acrylamide adduct solution is added78.8 parts of water. The resulting solution is adjusted to a pH of 7.4with sulfuric acid and then treated with 29.0 parts of 40 percentaqueous glyoxal. The resulting solution is heated at 50-55 C. for 155minutes, then cooled, diluted with parts of water and adjusted to a pHof 4.9 with sulfuric acid. The resulting solution of wet strength resincontains approximately 15.5 percent total solids.

Bleached kraft paper is prepared using the above wet strength resin.Samples of the paper are tested for wet strength as described in Example1 and the results of the tests are tabulated below. 4

Percentage of Resin Contained in Paper EXAMPLE 7 This example shows thepreparation and use of a wet strength resin prepared from isophthalicacid. To a mixture of 152.4 parts of tetraethylenepentamine and 40 partsof water is added 1 16.3 parts of isophthalic acid. The resultingmixture is heated to 170 C. and maintained between 170 and 177 C. for166 minutes, then heated to 213 C. during a period of 40 minutes andmaintained at a temperature between 213 and 225 C. for 50 additionalminutes. The resulting product is decanted into a pan and allowed tocool. The product has a reduced specific viscosity of approximately0.106. 62 parts of the aminopolyamide is dispersed in 186 parts of watercontaining approximately 0.55 parts of concentrated sulfuric acid. Themixture is treated with 56.9 parts of acrylamide, heated to 70 to 75 C.and held at this temperature for 3 hours. After cooling the solutioncontains approximately 40 percent total solids. The aboveaminopolyamideacrylamide adduct solution is diluted with 70.6 parts ofwater, adjusted to a pH of 7.5 with sulfuric acid and then treated with29 parts of 40 percent aqueous glyoxal. The resulting mixture is heatedto 54-55 C. and maintained at this temperature for about 75 minutes, atwhich time the mixture forms a light gel. The gel is dispersed by theaddition of approximately 103 parts of water, cooled and adjusted to apH of 4.55 with sulfuric acid. The resulting solution of wet strengthresin contains approximately 15.2 percent total solids and has aBrookfield viscosity of about 42.1 c.p.s. at 25 C.

Bleached kraft paper is prepared using the above wet strength resin asdescribed in Example 1. Samples of the paper are tested for wet strengthalso as described in Example 1 and the results are tabulated below.

Percentage of Resin Wet Tensile Percent This example shows thepreparation and use of a wet strength resin from theaminopolyamide-acrylamide adduct of Example 1 using glutaraldehyde inplace of glyoxal.

To 72.8 parts of the aminopolyamideacrylamide adduct solution describedin Example 1 is added 80 parts of 25 percent aqueous glutaraldehyde. Theresulting mixture is adjusted to a pH of 7.8 with sulfuric acid, andheated to 50 C. After 139 minutes at this temperature the resin reachesa viscosity of R on the Gardner-Holdt scale. The resin is diluted with129 parts of water, cooled and adjusted to a pH of 4.9 with sulfuricacid. The resulting resin solution contains approximately 16.5 percenttotal solids and has a Brookfield viscosity of55.6 c.p.s. at 25C.

Bleached kraft paper is prepared using the above wet strength resin asdescribed in Example 1. Samples of the paper are tested for wet strengthalso as described in Example 1 and the results tabulated below.

Percentage 01' Resin Wet Tensile Percent EXAMPLE 9 This example showsthe preparation and use of a wet strength resin usingdiethylenetriamine.

To 138.75 parts of diethylenetriamine is added 201 parts of adipic acid.The resulting mixture is heated to C. and maintained at a temperature ofbetween 165 and C. for minutes. The mixture is then cooled and dilutedto about 51.1 percent solids by the addition of water. The resultingaminopolyamide has a reduced specific viscosity of 0. 154. To 416.8parts of the above aminopolyamide solution is added 87.4 parts of waterand 78.2 parts of acrylamide. The mixture is heated at about 70-75 C.for 2 hours and then cooled. The resulting mixture containsapproximately 52.9 percent total solids. To 107.3 parts of the aboveaminopolyamide-acrylamide adduct solution is added 34.7 parts of water.The solution is adjusted to a pH of 7.5 using sulfuric acid and treatedwith 32.0 parts of 40 percent aqueous glyoxal. The resulting mixture isheated to 50 C. and held between about 50 C. and 60 C. for 4.1 hours. Atthe end of this time the Gardner-Holdt viscosity has increased tobetween E and F. The resin is cooled and diluted with about 290 parts ofwater and the pH adjusted to 5 with sulfuric acid. The resultingsolution of wet strength resin contains approximately 14.5 percent totalsolids and has a Brookfield viscosity of 7.1 c.p.s.

Bleached kraft paper is prepared from the above wet strength resin asdescribed in Example 1. Samples of the paper are tested for wet strengthalso as described in Example 1 and the results are tabulated below.

Percentage of Resin Wet Tensile Percent Contained in Paper of DryTensile None 1.8 0.5 5.2 1.0 6.8 2.0 9.0

Example 10 This example shows the preparation and use of wet strengthresin from an aminopolyamide treated with a small amount of dimethylsulfate.

To 189 parts of tetraethylenepentamine is added 146.1 parts of adipicacid and the mixture heated to 170 C. with stirring. The mixture ismaintained at a temperature of between about 168 and 172 C. for 42minutes, then the resin melt cooled to 140 C. and diluted withapproximately 292 parts of warm water. After cooling the resultingsolution contains about 51 percent solids and has a reduced specificviscosity of about 0.187. To 292.5 parts of the aminopolyamide solutionis added successively 305 parts of water and 106.7 parts of acrylamide.The resulting mixture is heated at 7075A C. for 2 hours and cooled. Theresulting solution contains 35.3 percent total solids. To 72.6 parts ofthe aminopolyamideacrylamide adduct solution is added 55.4 parts ofwater and 0.63 parts of dimethyl sulfate. The mixture is heated for 1hour at approximately 50 C. and then the pH adjusted to 7.5 withsulfuric acid. To this mixture is added 21.76 parts of 40 percentaqueous glyoxal and the resulting mixture heated to 50C. After 55minutes at a temperature of 5053 C. the viscosity of the solutionreaches a Gardner-Holdt value above S. The resulting resin is dilutedwith 200 parts of water and the pH adjusted to 5.0 with sulfuric acid.The resulting product contains approximately 9.9 percent solids and hasa Brookfield viscosity of 10.9 c.p.s. at 25 C.

Bleached kraft paper is prepared from the above wet strength resin asdescribed in Example 1. Samples of the paper are tested for both dry andwet strength after conditioning for over 24 hours at 73 F. and 50percent relative humidity. Wet tensile strengths are determined aftersoaking the paper for 10 seconds and also for 2 hours in distilled waterat room temperature. The results of these tests are tabulated below.

This example shows the use of the resin described in Example l as aflocculant.

A sample of the resin solution prepared in Example 1 is diluted withwater to 0.1 percent solids concentration. Various amounts of the 0.1percent solution are tested as a flocculant for aqueous suspensions ofmineral solids. In each case a 5 percent aqueous suspension of mineralsolids is placed in a 100 ml. graduated cylinder and treated with ameasured amount of resin solution. The thus treated suspension is mixedby rotating the graduated cylinder end-over-end twenty times. Thecylinder is set to rest and after 15 minutes the volume of supernatantliquid measured. A sample of the supernatant liquid is then withdrawnand tested for turbidity in a Klett- Summerson colorimeter. Controltests are conducted exactly the same way except no resin solution isadded. The specific mineral solid employed and the results of the testsare tabulated below b Average particle size about 5 microns. Averageparticle size about 1.] mlcrons.

EXAMPLE 12 This example shows the use of the resin described in Examplel as a retention aid in paper making.

A sample of the resin solution prepared in Example I is diluted withwater to 0.005 percent solids concentration. Various amounts of the0.005 percent solution are tested as a retention aid in making kraftpaper.

in each case bleached kraft pulp is beaten to 750 ml. freeness (S.R.) at2.5 consistency. An amount of pulp slurry equivalent to 75 parts of drypulp is adjusted to a pH of 6.5 with 10 percent H 80 7.5 parts of 10percent aqueous papermakers alum is added and the slurry adjusted to apH of 4.5. Kaolin filler is added in an amount of 7.5 parts and theslurry stirred for 5 minutes. The slurry is then diluted to 0.5 percentconsistency with water at a pH of 5 containing 60 ppm. of alum in theproportioner of a Noble-Wood handsheet machine. Portions of the slurryequivalent to about 2.5 parts of pulp are treated with measured amountsof the 0.005 percent resin solution and stirred 30 seconds. The thustreated slurries are diluted to 0.05 percent consistency in the decklebox of the handsheet machine and formed into handsheets. On some of thetest runs the alum is omitted and the pH adjusted to 8.0 with sodiumhydroxide. Control samples are run both with and without the alum.

The percentage of filler retained is calculated in each case from theash content of the handsheet and the ash content of the kaolin filler.The results of the tests are tabulated below.

Paper making Resin, percent Percent of Added Slurry of pulp FillerRetained pH 4.5 None 27 s (l percent alum) 0.0l Jl 0.05 SI 0.10 53 pH8.0 None I5 (no alum) 0.0] [8 0.05 35 0. [0 4| I claim:

I :in(CHz)mCHNHR where each R independently of each other is selectedfrom hydrogen and lower alkyl radicals, R is selected from hydrogen andamino substituted lower alkyl radicals, m is an integer from I to 5 andn is at least 1 with (b) an organic polybasic carboxylic acid oranhydride, in a ratio of from about 0.5 to about 2.0 moles ofpolyalkylene polyamine per mole of acid, with 2. an amount ofunsaturated amide, selected from the group consisting of acrylamide andlower alkyl substituted acrylamides, sufficient to react withsubstantially all of the primary and secondary amino groups in theaminopolyamide and 3. reacting the resulting amin0p0lyamideunsaturatedamide adduct with from about 0.05 to about 5.0 moles of an organiccompound containing at least two free aldehyde groups per mole ofunsaturated amide present in said adduct.

2. The product of claim 1 wherein the aminopolyamide is the reactionproduct of the condensation reaction of tetraethylenepentamine withadipic acid.

3. The product of claim 1 wherein the aminopolyamide is the reactionproduct of the condensation reaction of tetraethylenepentamine withitaconic acid.

4. The product of claim 1 wherein the aminopolyamide is the reactionproduct of the condensation reaction of tetraethylenepentamine withisophthalic acid.

5. The product of claim 1 wherein the organic compound containing atleast two free aldehyde groups is glyoxal.

6. The product of claim 1 wherein the organic compound containing atleast two free aldehyde groups is glutaraldehyde.

7. The product of claim 1 wherein the acrylamidc is a lower alkylsubstituted acrylamide.

8. The process of preparing an aminopolyamide-amylamide-polyaldehyderesin which comprises the steps of l. reacting a polyalkylene polyaminehaving the general formula selected from I l RHN (CHg CHN tCH l CHNHRand hydrogen and lower alkyl radicals, R is selected from hydrogen andamino substituted lower alkyl radicals, m is an integer from 1 to and nis at least I, with a polybasic carboxylic acid to form anaminopolyamide, in a ratio of from about 0.5 to about 2.0 moles ofpolyalkylene polyamine per mole of acid,

2) reacting the resulting aminopolyamide with an amount of unsaturatedamide, selected from the group consisting of aerylamide and lower alkylsubstituted acrylamides, sufficient to react with substantially all ofthe primary and secondary amino groups in the aminopolyamide, and,

3) reacting the resulting aminopolyamide-unsaturated amide adduct withfrom about 0.05 to about 5.0 moles per mole of unsaturated amide presentin said adduct of an organic compound containing at least two freealdehyde groups.

9. The process of claim 8 wherein up to 50 percent of the amine groupsin the aminopolyamide have been treated with an alkylating agentselected from the group consisting of alkyl sulfates and epihalohydrins.

10. The process of claim 8 wherein the polyalkylene polyamine is apolyethylene polyamine.

I]. The process of claim 10 wherein the polyethylene polyamine istetraethylenepentamine.

12. The process of claim 8 wherein the polybasic carboxylic acid is adicarboxylic acid.

13. The process of claim 12 wherein the dicarboxylic acid is adipicacid.

14. The process of claim 8 wherein the unsaturated amide is acrylamide.

15. The process of claim 8 wherein the organic compound containing atleast two free aldehyde groups is glyoxal.

16. A paper treating composition comprising an aqueous solution of up to15 percent solids by weight based on the weight of the water of theaminopolyamidc-aerylamidepolyaldehyde resin of claim 1.

17. Paper treated with from about 0.05 percent to about 5 percent byweight based on the weight of the paper of theaminopolyamideacrylamide--polyaldehyde resin of claim I to impart wetstrength.

18. The process of treating paper to impart wet strength which comprisestreating said paper with from about 0.05 percent to about 5 percent byweight based on the weight of the paper of theaminopolyamide-acrylamide-polyaldehyde resin of claim 1 and allowing thetreated paper to dry.

19. The process of claim 18 wherein said treating is conducted duringthe formation of said paper.

20. The process of floceulating solid particles suspended in water whichcomprises adding an amount of the aminopolyamideacrylamide-polyaldehyderesin of claim 1 to said suspension sufficicnt to flocculate saidparticles.

21. Paper treated with less than about 0.05 percent by weight based onthe weight of the paper of the aminopolyamidc-acrylamide-polyaldehyderesin of claim I to aid retention of mineral fillers.

22. The process of treating paper to aid the retention of mineralfillers which comprises treating said paper with less than about 0.05percent by weight based on the weight of the paper of theaminopolyamide-acrylamide-polyaldehyde resin of claim I and allowing thetreated paper to dry.

P0405) UNITED STATES PATENT OFFICE 5 CERTIFICATE OF CORRECTION PatentNo. 3,607,622 Dated September 21, 1971 Inventor) Herbert H. Espy It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Col. 3, line 11 of Printed Patent,- Page 6, line 12 of Spec.

"80C" should read -about 80C-- Col. 5, line 15 & 16 of Printed Patent;

"The resulting mixture is heated at 70 to 75C. for 2 hours and thencooled" is repeated.

Col. 7, line 21 of Printed Patent; Page 14, line 28 of Spec. Theword"Sixty-two" is omitted should read -Sixty-two (62) C01. 8, line 56of Printed Patent; Page 17, line 30 of Spec.

"70-75A C" should read -7075C- Col. 9, line 41 of Printed Patent; Page19, line 20 of Spec.

under the tabulation second column "260" should read --250-- Signed andsealed this L th day of April 1 972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Uttesting Officer Commissionerof Patents

2. The product of claim 1 wherein the aminopolyamide is the reactionproduct of the condensation reaction of tetraethylenepentamine withadipic acid.
 3. The product of claim 1 wherein the aminopolyamide is thereaction product of the condensation reaction of tetraethylenepentaminewith itaconic acid.
 4. The product of claim 1 wherein the aminopolyamideis the reaction product of the condensation reaction oftetraethylenepentamine with isophthalic acid.
 5. The product of claim 1wherein the organic compound containing at least two free aldehydegroups is glyoxal.
 6. The product of claim 1 wherein the organiccompound containing at least two free aldehyde groups is glutaraldehyde.7. The product of claim 1 wherein the acrylamide is a lower alkylsubstituted acrylamide.
 8. The process of preparing anaminopolyamide-acrylamide-polyaldehyde resin which comprises the stepsof
 9. The process of claim 8 wherein up to 50 percent of the aminegroups in the aminopolyamide have been treated with an alkylating agentselected from the group consisting of alkyl sulfates and epihalohydrins.10. The process of claim 8 wherein the polyalkylene polyamine is apolyethylene polyamine.
 11. The process of claim 10 wherein thepolyethylene polyamine is tetraethylenepentamine.
 12. The process ofclaim 8 wherein the polybasic carboxylic acid is a dicarboxylic acid.13. The process of claim 12 wherein the dicarboxylic acid is adipicacid.
 14. The process of claim 8 wherein the unsaturated amide isacrylamide.
 15. The process of claim 8 wherein the organic compoundcontaining at least two free aldehyde groups is glyoxal.
 16. A papertreating composition comprising an aqueous solution of up to 15 percentsolids by weight based on the weight of the water of the aminopolyamide-acrylamide- polyaldehyde resin of claim
 1. 17. Paper treated with fromabout 0.05 percent to about 5 percent by weight based on the weight ofthe paper of the aminopolyamide- acrylamide- polyaldehyde resin of claim1 to impart wet strength.
 18. The process of treating paper to impartwet strength which comprises treating said paper with from about 0.05percent to about 5 percent by weight based on the weight of the paper ofthe aminopolyamide- acrylamide- polyaldehyde resin of claim 1 andallowing the treated paper to dry.
 19. The process of claim 18 whereinsaid treating is conducted during the formation of said paper.
 20. Theprocess of flocculating solid particles suspended in water whichcomprises adding an amount of the aminopolyamide-acrylamide-polyaldehyde resin of claim 1 to said suspension sufficient toflocculate said particles.
 21. Paper treated with less than about 0.05percent by weight based on the weight of the paper of theaminopolyamide-acrylamide-polyaldehyde resin of claim 1 to aid retentionof mineral fillers.
 22. The process of treating paper to aid theretention of mineral fillers which comprises treating said paper withless than about 0.05 percent by weight based on the weight of the paperof the aminopolyamide-acrylamide-polyaldehyde resin of claim 1 andallowing the treated paper to dry.